US7424519B2 - Distributed storage system, storage device and method of copying data - Google Patents

Distributed storage system, storage device and method of copying data Download PDF

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US7424519B2
US7424519B2 US10/194,316 US19431602A US7424519B2 US 7424519 B2 US7424519 B2 US 7424519B2 US 19431602 A US19431602 A US 19431602A US 7424519 B2 US7424519 B2 US 7424519B2
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data
storage device
storage
storage devices
network
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US20030131068A1 (en
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Kazuyoshi Hoshino
Hiroaki Odawara
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Hitachi Ltd
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    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/06—Digital input from, or digital output to, record carriers, e.g. RAID, emulated record carriers or networked record carriers
    • G06F3/0601—Interfaces specially adapted for storage systems
    • G06F3/0602—Interfaces specially adapted for storage systems specifically adapted to achieve a particular effect
    • G06F3/061—Improving I/O performance
    • G06F3/0613—Improving I/O performance in relation to throughput
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/16—Error detection or correction of the data by redundancy in hardware
    • G06F11/20—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
    • G06F11/2053—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements where persistent mass storage functionality or persistent mass storage control functionality is redundant
    • G06F11/2056—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements where persistent mass storage functionality or persistent mass storage control functionality is redundant by mirroring
    • G06F11/2082—Data synchronisation
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/06—Digital input from, or digital output to, record carriers, e.g. RAID, emulated record carriers or networked record carriers
    • G06F3/0601—Interfaces specially adapted for storage systems
    • G06F3/0628—Interfaces specially adapted for storage systems making use of a particular technique
    • G06F3/0629—Configuration or reconfiguration of storage systems
    • G06F3/0635—Configuration or reconfiguration of storage systems by changing the path, e.g. traffic rerouting, path reconfiguration
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/06—Digital input from, or digital output to, record carriers, e.g. RAID, emulated record carriers or networked record carriers
    • G06F3/0601—Interfaces specially adapted for storage systems
    • G06F3/0628—Interfaces specially adapted for storage systems making use of a particular technique
    • G06F3/0646—Horizontal data movement in storage systems, i.e. moving data in between storage devices or systems
    • G06F3/065—Replication mechanisms
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/06—Digital input from, or digital output to, record carriers, e.g. RAID, emulated record carriers or networked record carriers
    • G06F3/0601—Interfaces specially adapted for storage systems
    • G06F3/0668—Interfaces specially adapted for storage systems adopting a particular infrastructure
    • G06F3/067—Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/06—Digital input from, or digital output to, record carriers, e.g. RAID, emulated record carriers or networked record carriers
    • G06F3/0601—Interfaces specially adapted for storage systems
    • G06F3/0668—Interfaces specially adapted for storage systems adopting a particular infrastructure
    • G06F3/0671—In-line storage system
    • G06F3/0683—Plurality of storage devices
    • G06F3/0689—Disk arrays, e.g. RAID, JBOD
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/16—Error detection or correction of the data by redundancy in hardware
    • G06F11/20—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
    • G06F11/2053—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements where persistent mass storage functionality or persistent mass storage control functionality is redundant
    • G06F11/2056—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements where persistent mass storage functionality or persistent mass storage control functionality is redundant by mirroring
    • G06F11/2069—Management of state, configuration or failover

Definitions

  • the present invention relates to a data storage, and in particular, to a distributed storage and a system using the same.
  • RAID redundant array of independent disks
  • remote copy To protect data, a method called “redundant array of independent disks (RAID)” or “remote copy” has been heretofore employed.
  • the RAID system is classified into RAID-0 to RAID-5.
  • RAID-0 and RAID-5 are mainly used at present.
  • the data to be protected is written on a current disk and another or backup disk. Even if the current disk fails, the data thereon is also written on the backup disk. It is therefore possible to prevent loss of data.
  • record data divided into blocks and parity of the record data are distributed to be recorded on a plurality of disks.
  • the record data on the disk can be restored using associated data and data parity stored on other normal disks. Also, since data can be distributively written on or read from the disks in a concurrent fashion in the RAID-5 system, the disk access speed is increased when compared with a disk access operation using one disk.
  • a remote copy method is used to produce a replica or copy of data at a physically remote location using a network.
  • the remote copy is achieved, for example, in a configuration in which servers are coupled via a network with each other or a configuration in which storage subsystems are coupled via a network with each other.
  • a leased communication line with guaranteed communication quality is primarily employed as the network for the remote copy.
  • the RAID system is commonly used to protect data.
  • the data is protected between the disks belonging to the servers or within a storage subsystem linked with servers via a storage area network (SAN). Therefore, data cannot be protected in the local disaster.
  • SAN storage area network
  • a leased line is used in general.
  • a high communication cost is required for the leased line. Therefore, a considerably high cost is required to backup a large amount of data.
  • a relatively inexpensive network such as internet can be used for the remote copy.
  • the backup system is possibly disabled by deteriorated communication quality (by a decreased communication speed) in some cases. Therefore, a system or a method to overcome this difficulty is required.
  • At least three storage devices are connected via a network to each other. From one copy source storage device, backup data is concurrently transferred to a plurality of copy destination storage devices to thereby implement high-speed backup.
  • a data copy method in which a plurality of storage devices are mutually connected via a network to each other such that a copy of data in a source storage device is produced in a plurality of storage devices other than the source storage device.
  • storage devices are selected to generate thereof a copy of data from a storage device.
  • the state of communication connection of the network can be determined using a packet monitoring the network state.
  • Each storage device includes a data input buffer to transmit a data frame for each communication connection to the other storage devices.
  • the storage device can therefore determine the state of communication connection of the network according to a state of the data input buffer.
  • there may be used various modes such as a mode in which data is preferentially sent to a buffer having a larger unused area and a mode in which data is preferentially sent to a buffer having a higher transmission rate.
  • a distributed storage system in which a host computer is connected via a network to a plurality of storage devices. According to a state of communication connection of the network, storage devices to be accessed by the host computer is dynamically selected.
  • a storage device connected via a network to other storage devices to communication to each other. According to a state of communication connection of the network, the storage device dynamically selects another storage device to be accessed.
  • FIG. 1 is a diagram showing a configuration of a distributed storage system.
  • FIG. 2 is a block diagram showing a configuration of a storage device.
  • FIG. 3 is a flowchart showing a procedure to write data from a host computer to a storage device.
  • FIGS. 4A to 4D are diagrams showing layouts of frames used to transfer data.
  • FIG. 5 is a diagram showing a configuration of a network interface.
  • FIG. 6 is a diagram showing a local management table.
  • FIGS. 7A and 7B are diagrams showing remote management tables.
  • FIG. 8 is a flowchart ( 1 ) showing operation of a local interface to write data.
  • FIG. 9 is a flowchart ( 2 ) showing operation of a local interface to write data.
  • FIG. 10 is a flowchart ( 3 ) showing operation of a local interface to write data.
  • FIG. 11 is a flowchart ( 4 ) showing operation of a local interface to write data.
  • FIG. 12 is a flowchart showing operation to transfer data from a local device to a remote device.
  • FIG. 13 is a flowchart showing operation to transfer data from a host computer to a storage device.
  • FIG. 14 is a flowchart showing operation to restore original data at failure of a recording or storage medium.
  • FIG. 15 is a flowchart showing operation to transfer a failure data table to backup replica data at failure of a storage medium.
  • FIG. 16 is a flowchart showing operation to transfer data to backup replica data at failure of a storage medium.
  • FIG. 17 is a diagram showing a configuration of a failure data table.
  • FIG. 18 is a flowchart showing operation to transfer a failure data table to restore original data at failure of a storage device.
  • FIG. 19 is a flowchart showing operation to transfer data to restore original data at failure of a storage device.
  • FIG. 1 shows the overall configuration of a distributed storage system according to the present invention.
  • the configuration is an example of a distributed storage system including three storage devices 1 to 3 mutually connected via a network 4 to each other and four host computers 5 to 8 connected to the storage devices 1 to 3 as shown in FIG. 1 .
  • the storage devices 1 to 3 can be directly connected to the host computers 5 to 8 using a cable or an optical fiber or using storage area network (SAN). It is also possible to configure the system such that the host computers 5 to 8 includes the storage devices 1 to 3 and the host computers 5 to 8 are connected to the storage devices 1 to 3 using an internal bus.
  • SAN storage area network
  • FIG. 2 shows an example of a configuration of the storage device 1 .
  • the storage devices 2 and 3 may be configured in the same way as for the storage device 1 .
  • the storage device 1 includes a storage controller 9 and a storage box 10 .
  • the storage controller 9 is connected via a data transfer channel 11 .
  • the storage device 1 is connected via two host interfaces 12 - 1 and 12 - 2 respectively to the host computers 5 and 6 and is connected via two storage interfaces 13 - 1 and 13 - 2 to the storage box 10 .
  • the storage device 1 is mutually connected via a network interface 14 and a network 4 to the storage devices 2 and 3 .
  • the cache memory 15 is used to write data in the storage device 10 and to temporarily store readout data therein.
  • the host interfaces 12 , the storage interfaces 13 , network interface 14 , and the cache memory 15 are mutually connected via an internal bus 16 in the storage controller 9 .
  • Each of the host computers 5 and 6 issues, in response to a request from a process such as an operating system or an application, an access instruction or command via the host interface 12 to the storage controller 9 .
  • the controller 9 controls via the storage interface 13 a recording medium 17 of the storage device 10 according to the access command from the host computer 5 or 6 to achieve a data write or read operation.
  • FIG. 3 shows an example of a data write procedure between the host computer 5 and the storage device 1 .
  • the host computer 5 issues a data write command frame 18 to the storage device 1 .
  • FIG. 4 shows an example of each frame used for the data transfer operation of FIG. 3 .
  • the host computer 5 issues a data write command frame 18 ( FIG. 4A ) to the storage device 1 to instruct a data write operation.
  • a command of the command frame 18 from a transmission source storage device to a destination storage device is written as a command operation code in a command field 29 ( FIG. 4A ).
  • the host interface 12 - 1 reserves a data receiving area in the cache memory 15 according to information of transfer data in a the command field 29 of the command frame 18 and then sends a transfer ready frame 19 ( FIG. 4B ) to the host computer. Having received the frame 19 , the host computer 5 outputs a data frame 20 ( FIG. 4C ) to the storage device 1 . The host interface 12 writes the data from the host computer 5 via the bus 16 in the cache memory 15 and sends the transfer ready frame 19 to the host computer to request transfer of a next data frame 19 . If the received data frame is a last data frame 19 or if a reception error occurs, the host interface 12 sends to the host computer 5 a response frame 21 ( FIG.
  • the host interface 12 also sends to the storage interface 13 and the network interface 12 information such as a logical unit number 28 of the write data, such contents of the command 29 as a logical address, a data transfer length, a timestamp indicating data write time, and a data storage area address in the cache memory 15 .
  • a frame header 22 of each frame contains a sequence identifier 26 to identify a transfer sequence of each data, a sequence number 27 indicating an order of the frame in the sequence, and a destination address 24 and a source address 25 to respectively identify a host computer 5 and a storage device 1 respectively as a transmission destination and a transmission source.
  • the address layout varies according to the network to connect the host computer 5 to the storage device 6 .
  • the identifiers are set to the destination and source addresses 24 and 25 .
  • the network is Ethernet, a trademark of Fuji-Xerox, MAC addresses are set thereto.
  • IP addresses are set thereto.
  • the storage interface 13 converts the logical unit number 18 into a physical unit number of the storage medium 17 , converts a logical address of the storage medium 17 into a physical address thereof, and read data via the bus 16 from the cache memory 15 . Finally, the storage interface 13 writes data via the data transfer channel 11 on the storage medium 17 .
  • the network interface 14 copies write data received via the network 4 from the host computer 5 distributively onto the storage devices 2 and 3 of the distributed storage system.
  • the copy can be used as backup data.
  • FIG. 5 shows an example of the configuration of the network interface 14 .
  • the configuration of the interface 14 shown in FIG. 5 includes a bus controller 33 , a processor 34 , a memory 35 , a frame sender 36 , and a frame receiver 37 .
  • the bus controller 33 arbitrates the bus 16 to communicate data via the bus 16 with other constituent components of the storage controller 9 .
  • the processor 34 conducts processing for communication connections to the storage devices 2 and 3 of the distributed storage system. For example, the processor 34 sets, maintains, and manages the communication connections as well as controls data transfer flows and determines the data transmission destination.
  • the memory 35 stores programs to be executed by the processor 34 , a local management table 42 to manage data transferred to the storage devices 2 and 3 of the distributed storage system, and a remote management table 43 to manage data transferred from the storage devices of the distributed storage system.
  • the memory 35 also stores a failure data table 44 to restore erroneous data at occurrence of a failure.
  • the frame sender 36 includes a data-in-buffer 38 to send a data frame for each communication connection for the storage devices 2 and 3 of the distributed storage system and a command-in-buffer 39 to transmit a command frame 18 or a control frame such as “TCP Ack frame” of a data transfer flow.
  • the frame receiver 37 also a data-out-buffer 40 to receive a data frame for each communication connection for the storage devices 2 and 3 of the distributed storage system and a command-in-buffer 39 to receive a command frame 18 or a control frame of a data transfer flow.
  • FIG. 6 shows a configuration example of the local management table
  • FIG. 7 shows a configuration example of the remote management table 43 .
  • the storage device 1 notifies the storage devices 2 and 3 of the distributed storage system that the device 1 starts operating as “a storage device 1 ” of the distributed storage system. Having received the notification, each of the storage devices 2 and 3 registers the storage device 1 having issued the notification as a constituent component of the distributed storage system and then returns a reply of completion of the registration to the storage device 1 . On receiving the reply, the device 1 confirms the storage devices 2 and 3 effectively operating in the distributed storage system and communicates data with the storage devices 2 and 3 having sent the reply to the device 1 . In this connection, the notification-reply processing may be periodically executed at a fixed interval of time to confirm that the storage devices 2 and 3 are normally operating in the distributed storage system.
  • the storage device 1 may use a method in which the system manager beforehand establishes a notification destination list or a method in which an enquiry is sent to a representative server to which the notification destination list is beforehand registered. If the network 4 mutually connected the storage devices 1 to 3 to each other supports a multicast or broadcast operation, the notification can be multicasted or broadcasted without paying attention to the notification destinations.
  • a method to fixedly set and maintain the communication connection such as a permanent virtual connection (PVC) in an asynchronous transfer mode (ATM) network or a method in which each communication connection is dynamically set when a data transfer is started and the connection is disconnected when the data transfer is completed, for example, a transmission control protocol (TCP) connection in an internet protocol (IP) network.
  • PVC permanent virtual connection
  • ATM asynchronous transfer mode
  • TCP transmission control protocol
  • IP internet protocol
  • a storage device as a data copy source is called a local storage device and a storage device as a data copy destination is called a remote storage device hereinbelow.
  • Data written from the host computer in the local storage device is called original data and data written from the local storage device in the remote storage device is called replica data.
  • FIGS. 8 to 12 show, as an example of the data copy operation from the local storage device to the remote storage device, a copy operation to copy data from the storage device 1 onto the storage device 2 .
  • FIGS. 8 to 11 show an operation example of the network interface 14 of the storage device 1 at transmission of data in flowcharts.
  • the host interface 12 notifies to the network interface 14 such items as a logical unit number, a logical address, and a data transfer length of write data, a time stamp indicating data write time, and a data storage area address on the cache memory 15 .
  • the processor 34 makes a search through the local management table 42 to determine whether or not an entry of the logical unit number and the logical address of the notified data exists in the local management table 42 ( 46 ). If the entry is absent, the processor 34 confirms a state of each data-in-buffer 38 ( 47 ) to detect a data-in-buffer 38 available for data transmission. For example, if data transmission is impossible from any data-in-buffer 38 because of another data write operation, the processor 34 waits for a state in which the data write operation is finished and hence a data-in-buffer 38 becomes available ($( ).
  • a data-in-buffer 38 is selected for transmission according to a predetermined procedure, for example, a round-robin procedure, a random procedure, or a procedure to preferentially use a data-in-buffer 38 with a smaller amount of total transfer data ( 49 ).
  • the processor 34 preferentially select, as the data transfer destination, a transfer destination remote storage device described in the old entry ( 56 to 59 ) for the following reasons. If the data is transferred to a remote storage device other than that described in the old entry, a plurality of data having the logical unit number and the logical address exists in the distributed storage device. When the data can be transferred to the remote storage device described in the old entry, the write data is written in the area occupied by old data before. This prevents the situation in which a plurality of data having the logical unit number and the logical address exists in the distributed storage device.
  • the processor 34 selects a data-in-buffer 38 corresponding to a remote storage device other than that described in the old entry ( 60 to 63 ). In this case, to prevent duplication of the data, the processor 34 must transfer, after the data transfer to the remote storage device other than that described in the old entry is finished, a command frame 18 to the remote storage device described in the old entry such that the data area of the logical unit and the logical address indicated by the old entry is released and the entry corresponding to the released data area is erased in the remote management table 43 ( 68 ).
  • the processor 34 checks the state of the TCP connection of the selected buffer 38 ( 50 , 64 ). If the TCP connection has not been established, a three-directional handshake operation is conducted with the selected remote storage device to set the TCP connection ( 5 a , 65 ).
  • the local storage device transfers data to the remote device ( 53 , 67 ).
  • FIG. 12 shows an example of a data write procedure between the storage device 1 and the storage device 2 . It is assumed in the description that each of the frames 18 to 21 communicated between the storage devices 1 to 3 via the network 4 is processed as follows.
  • the frame In the data-in-buffer 38 of the storage device on the transmission side, the frame is divided into a plurality of blocks according to a maximum packet length allowed by the network 4 . Thereafter, such headers as a layer-2 header, an IP header, and a TCP header are added thereto to be send as an IP packet via the network.
  • the headers including a layer-2 header, an IP header, and a TCP header are removed from the packet such that a frame is configured as a result.
  • the IP packet communication via the network 4 is controlled according to a TCP window.
  • the storage device 1 sends a write command frame 18 to the storage device 2 . Having received the frame 18 , the storage device 2 reserves a buffer with a storage capacity necessary to receive data and then returns a transfer ready frame 19 to the storage device 1 . Having received the frame 19 , the storage device 1 transfers write data (data frame 20 ) beginning at a data write address of the cache memory 15 indicated by the host interface 12 to the selected data-in-buffer 38 . The data is resultantly sent to the storage device 2 .
  • the storage device 2 transfers the received data frame 20 to a buffer area in the cache memory 15 beforehand reserved and sends the transfer ready frame 19 to the local storage device 1 to request a next data transfer. If the received data frame is a last data frame 20 or if a reception error occurs, the storage device 2 sends a response frame 21 indicating a reception status to the storage device 1 to thereby terminate the data transfer. If a data write notification is not received from the host interface 12 , the storage device 2 disconnects the TCP connection.
  • the network interface 14 of the storage device 2 After the data frame 20 is written in the cache memory 15 , the network interface 14 of the storage device 2 notifies to the storage controller 13 items including a logical unit number, a logical address, and a data transfer length of the write data and a cache memory area having temporarily stored the data. Having received the notification from the network interface 14 , the storage controller 13 conducts various operations, for example, converts the logical unit number into a physical unit number, converts the logical address into a physical address, and reads data via the bus 16 from the cache memory 15 . Finally, the storage controller 13 writes data via the data transfer channel 11 in the storage medium 17 .
  • the network interface 14 of the storage device 1 describes in the local management table 42 in the memory 35 an entry including an identifier of the storage device 2 as the data transfer destination, a logical unit number and a logical address of the write data, and a time stamp.
  • the storage device 2 describes in the remote management table 43 an entry including an identifier of the storage device 1 as the data transfer source, a logical unit number and a logical address of the write data, and a time stamp.
  • FIGS. 6 and 7 shows configuration examples of the local management table 42 and the remote management table 43 , respectively.
  • the original data written from the host computer in the storage device can be stored as replica data in a remote storage device while dynamically changing an amount of transfer data depending on the state of the communication connection between the storage devices.
  • the amount of transfer data is controlled by the TCP window.
  • the amount of transfer data to each remote storage device can also be changed by using a packet to monitor the state of the network, for example, in the ATM available bit rate (ABR) service.
  • ABR ATM available bit rate
  • FIG. 13 shows an example of a data read procedure between a host computer and a storage device.
  • the storage device 1 Having received the data read command frame from the host computer 5 , the storage device 1 makes a search through the cache memory 15 to determine whether or not the data requested by the host computer 5 is present in the memory 15 . If the data is present therein, the storage device 1 reads the data from the memory 15 adds a frame header to the data and then sends a data frame 20 including the data to the host computer 5 . If the data is absent, the storage device 1 transfers the data from the storage medium 17 via the storage controller 13 to the cache memory 15 . The storage device 1 sends the data frame 20 to the host computer A in a procedure similar to that described above. When the frame 20 is completely transmitted, the storage device 1 sends a response frame 32 including a state of the data frame transmission to the host computer A to thereby terminates the data read operation.
  • Each of the storage devices 1 to 3 of the distributed storage system reads, when a failure occurs on a storage medium thereof, replica data beforehand stored as backup data in another storage device to restore the original data written on the failed storage medium from the host computer. Simultaneously, the storage device instructs another storage device such that the replica data written on the failed storage medium is again copied as backup data.
  • FIG. 14 shows a procedure in which the storage device 1 of which a failure occurs on the storage medium 17 reads the replica data beforehand stored as backup data on the storage devices 2 and 3 and restores the original data written on the failed storage medium 17 .
  • the storage device 1 Using the conversion table between the logical unit number and the physical unit number and between the logical address and the physical address and the local management table which are managed by the storage interface 13 , the storage device 1 identifies a backup destination of the original data written on the failed storage medium 17 and sends a replica data readout command frame 18 to the storage devices 2 and 3 .
  • each of the storage devices 2 and 3 makes a search through the cache memory 15 to determine whether or not the requested data is present therein. If the data is present in the memory 15 , the storage device reads the data from the memory 15 and sends a data frame 20 including the data to the storage device 1 associated with the failed storage medium. If the data is absent, the storage device transfers the data from the storage medium 17 via the storage controller 13 to the cache memory 15 and then sends the data frame 20 to the storage device 1 . Having received the data transferred from the storage device 2 and 3 , the device 1 writes the data via the cache memory 15 and the storage interface 13 on the storage device 17 for the recovery thereof.
  • the storage device 1 can restore the original data written on the failed storage medium. If a data readout request is issued from the host computer 5 to the failed storage medium 17 before the medium 17 is completely restored, the storage device 1 can naturally read the replica data of the requested data from the remote storage devices 2 and 3 .
  • FIGS. 15 and 16 shows a procedure in which the replica data written on the failed storage medium of the storage device 1 is again produced as backup data using the storage device 2 .
  • FIG. 15 shows an example of a procedure to transfer a failure data table from the storage device 1 to the storage device 2 .
  • the storage device 1 of which the storage medium fails produces a failure data table 44 as a list of replica data written from the storage device 2 onto the failed storage medium 17 .
  • FIG. 17 shows an example of the failure data table 44 .
  • the storage device 2 which writes replica data in the storage device 1 requests the storage device 1 to notify a table size of the failure data table 44 including a list of data written on the failed storage medium. Having received the table size notification, the storage device 1 accesses the conversion table between the logical unit number and the physical unit number and between the logical address and the physical address and the remote management table 43 which are managed by the storage interface 13 and then produces a failure data table 44 as a list of replica data written from the storage device 2 onto the failed storage medium of the storage device 1 . The storage device 1 then sends a data frame 31 including the table size of the failure data table and a response frame 21 to the storage device 2 .
  • the storage device 2 reserves in the memory 35 of the network interface 14 a memory having a capacity to write the failure data table and then sends a transfer request command frame 18 for the failure data table 44 to the storage device 1 .
  • the storage device 1 sends a data frame 20 including the failure data table 44 and a response frame 21 to the storage device 2 .
  • the storage device 2 writes the table 44 in a memory 31 of the network interface 14 .
  • the storage device 2 then makes a search through the cache memory 35 to determine whether or not data associated with the logical unit number and the logical address indicated by any entry of the failure data table 44 is present therein. If the data is present in the memory 35 , the storage device 2 reads the data from the memory 35 and then copies the data as backup data on the storage devices 1 and 3 as remote storage devices of the storage device 2 in a data transfer procedure shown in FIG. 12 . If the data is absent, the storage device 2 transfers the data via the storage interface 13 to the cache memory 35 and then sends a data frame 31 to the storage device 1 or 3 in a procedure similar to that described above. In this operation, the remote storage as the data transfer destination need not be the storage device 1 of which the storage medium fails. It is to be appreciated that the storage device 3 can be similarly used to again produce replica data as the backup data written on the failed storage medium of the storage device 1 .
  • either one of the normal storage devices which is beforehand registered as a master storage device reads the replica data beforehand stored by the failed storage device as backup data on another storage device to thereby restore the original data.
  • FIGS. 18 and 19 shows an example of operation conducted between the storage devices 2 and 3 at occurrence of a failure in the storage device 1 .
  • the distributed storage system sets a predetermined remote storage device 2 as a master storage device and any other storage device (only the storage device 3 in FIGS. 14 and 15 ) to a slave storage device to restore the original data.
  • the storage device 2 as the master device accesses the remote management table 43 to generate therefrom a failure data table 44 as a lit of replica data written from the storage device 1 in the storage device 2 .
  • the storage device 2 sends a command frame 18 for a table size transfer to the storage device 3 as the slave device to send a table size of the failure data table 4 as a list of replica data written from the storage device 1 in the storage device 3 .
  • the storage device 3 accesses the remote management table 43 to generated therefrom a failure data table 44 as a lit of replica data written from the storage device 1 in the storage device 3 .
  • the storage device 3 then sends a data frame 20 including the size of the generated table 44 and a response frame 21 to the storage device 2 .
  • the storage device 2 On receiving the data frame 20 including the table size of the failure data table 44 from the storage device 3 , the storage device 2 reserves in the memory 35 of the network interface an area of a capacity to store the failure data table 44 of the storage device 3 and then sends a transfer request command frame 18 to the storage device 3 to transfer the failure table 44 . Having received the command frame 18 , the storage device 3 sends a data frame including the failure data table 44 and a response frame 21 to the storage device 2 . On receiving the data frame 20 , the storage device 2 combines a failure data table 44 of the storage device 2 with the failure data table 44 from the storage device 3 to thereby restore a local management table 44 kept by the failed storage device 1 .
  • a time stamp of the table 44 of the storage device 2 is compared with that of the table 44 from the storage device 3 to select an entry with a younger time stamp. This resultantly prevents duplication of data.
  • the storage device 2 as the master device restores the original data kept in the storage device 1 using the replica data read from the storage device and the replica data kept in the storage device 2 .
  • the storage device as the master copies again as backup data the replica data of the storage device 1 kept by the storage device 2 onto each storage device (only the storage device 3 in the embodiment) according to a procedure similar to that shown in FIG. 9 .
  • the storage device 2 and the host computer 7 can resume the data processing in place of the storage device 1 and the host computer 5 which are interrupted by the failure.
  • the data backup operation and the data restoration can be achieved at a high speed.

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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080205441A1 (en) * 2003-05-08 2008-08-28 Scott Furey Data frame processing
US20090077232A1 (en) * 2003-10-14 2009-03-19 International Business Machines Corporation Remote activity monitoring
US20100036850A1 (en) * 2008-08-08 2010-02-11 Garman Matthew S Providing executing programs with reliable access to non-local block data storage
US20100082995A1 (en) * 2008-09-30 2010-04-01 Brian Dees Methods to communicate a timestamp to a storage system
US20100199000A1 (en) * 2009-02-05 2010-08-05 Htc Corporation Data storage device and method for operating the same
US20110320509A1 (en) * 2010-06-29 2011-12-29 France Telecom Managing the site where data is stored in a distributed storage system
US20120203794A1 (en) * 2011-02-09 2012-08-09 Roulei Zhang Efficiently delivering event messages using compiled indexing and paginated reporting
US8949614B1 (en) * 2008-04-18 2015-02-03 Netapp, Inc. Highly efficient guarantee of data consistency
US20150286537A1 (en) * 2014-04-02 2015-10-08 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US9483361B2 (en) 2013-05-08 2016-11-01 Commvault Systems, Inc. Information management cell with failover management capability
US10534673B2 (en) 2010-06-04 2020-01-14 Commvault Systems, Inc. Failover systems and methods for performing backup operations
US11200124B2 (en) 2018-12-06 2021-12-14 Commvault Systems, Inc. Assigning backup resources based on failover of partnered data storage servers in a data storage management system
US11429499B2 (en) 2016-09-30 2022-08-30 Commvault Systems, Inc. Heartbeat monitoring of virtual machines for initiating failover operations in a data storage management system, including operations by a master monitor node
US11449394B2 (en) 2010-06-04 2022-09-20 Commvault Systems, Inc. Failover systems and methods for performing backup operations, including heterogeneous indexing and load balancing of backup and indexing resources
US11645175B2 (en) 2021-02-12 2023-05-09 Commvault Systems, Inc. Automatic failover of a storage manager
US11663099B2 (en) 2020-03-26 2023-05-30 Commvault Systems, Inc. Snapshot-based disaster recovery orchestration of virtual machine failover and failback operations
US12360942B2 (en) 2023-01-19 2025-07-15 Commvault Systems, Inc. Selection of a simulated archiving plan for a desired dataset

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI282053B (en) * 2002-06-19 2007-06-01 Quanta Comp Inc Data reading/writing method by calling for service routine of basic input/output system
US7103727B2 (en) 2002-07-30 2006-09-05 Hitachi, Ltd. Storage system for multi-site remote copy
JP4452438B2 (ja) * 2002-11-11 2010-04-21 株式会社日立製作所 記憶システム
JP2005108098A (ja) * 2003-10-01 2005-04-21 Hitachi Ltd データｉ／ｏ装置及びデータｉ／ｏ装置の制御方法
US7613785B2 (en) * 2003-11-20 2009-11-03 International Business Machines Corporation Decreased response time for peer-to-peer remote copy write operation
JP4489455B2 (ja) * 2004-02-16 2010-06-23 株式会社日立製作所 ディスク制御装置及びディスク制御装置の制御方法
WO2005101241A2 (en) * 2004-04-13 2005-10-27 Alon Tavori Method for depositing and retrieving digital records
US7529781B2 (en) * 2004-04-30 2009-05-05 Emc Corporation Online initial mirror synchronization and mirror synchronization verification in storage area networks
US7827144B1 (en) * 2005-11-17 2010-11-02 Hewlett-Packard Development Company, L.P. Methods of reading and writing data
US8595313B2 (en) * 2005-11-29 2013-11-26 Netapp. Inc. Systems and method for simple scale-out storage clusters
US8156174B2 (en) 2007-04-13 2012-04-10 Platform Computing Corporation Method and system for information exchange utilizing an asynchronous persistent store protocol
JP2008305073A (ja) * 2007-06-06 2008-12-18 Hitachi Ltd ファイル共有システム及びファイル共有装置の起動方法
US9454325B2 (en) * 2009-11-04 2016-09-27 Broadcom Corporation Method and system for offline data access on computer systems
US8903906B2 (en) * 2010-03-16 2014-12-02 Brother Kogyo Kabushiki Kaisha Information communications system, node device, method of communicating contents, computer readable recording medium storing a program
WO2012095848A2 (en) 2011-01-10 2012-07-19 Storone Ltd. Large scale storage system
EP2864885B1 (en) 2012-06-25 2017-05-17 Storone Ltd. System and method for datacenters disaster recovery
US9612851B2 (en) 2013-03-21 2017-04-04 Storone Ltd. Deploying data-path-related plug-ins
US10019203B1 (en) * 2013-05-30 2018-07-10 Cavium, Inc. Method and system for processing write requests
US10365848B2 (en) 2015-12-02 2019-07-30 Netapp, Inc. Space reservation for distributed storage systems
JP6458752B2 (ja) * 2016-03-04 2019-01-30 日本電気株式会社 ストレージ制御装置、ストレージシステム、ストレージ制御方法、および、プログラム
JP6930506B2 (ja) * 2018-08-08 2021-09-01 株式会社Ｊｖｃケンウッド データ記録送信装置、データ記録送信方法、及びデータ記録送信プログラム

Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1124846A (ja) 1997-07-03 1999-01-29 Hitachi Ltd ネットワークを利用したバックアップシステム
US5966730A (en) * 1996-10-30 1999-10-12 Dantz Development Corporation Backup system for computer network incorporating opportunistic backup by prioritizing least recently backed up computer or computer storage medium
US6101497A (en) * 1996-05-31 2000-08-08 Emc Corporation Method and apparatus for independent and simultaneous access to a common data set
US6108300A (en) * 1997-05-02 2000-08-22 Cisco Technology, Inc Method and apparatus for transparently providing a failover network device
US20010020254A1 (en) * 1998-06-30 2001-09-06 Blumenau Steven M. Method and apparatus for managing access to storage devices in a storage system with access control
US20010056438A1 (en) * 2000-06-27 2001-12-27 Atsuki Ito Database system with backup and recovery mechanisms
US6356977B2 (en) * 1995-09-01 2002-03-12 Emc Corporation System and method for on-line, real time, data migration
US20020161845A1 (en) * 2001-04-30 2002-10-31 Odenwald Louis H. Selectable logical identifier mapping
US20020176430A1 (en) * 2001-01-25 2002-11-28 Sangha Onkar S. Buffer management for communication systems
US20030084076A1 (en) * 2001-10-31 2003-05-01 Shihoko Sekiguchi Method for storage management of storage resource on a storage network
US20030120723A1 (en) * 2001-12-20 2003-06-26 Bright Jonathan D. System and method for distributed network data storage
US20030126200A1 (en) * 1996-08-02 2003-07-03 Wolff James J. Dynamic load balancing of a network of client and server computer
US20030126282A1 (en) * 2001-12-29 2003-07-03 International Business Machines Corporation System and method for improving backup performance of media and dynamic ready to transfer control mechanism
US6785678B2 (en) * 2000-12-21 2004-08-31 Emc Corporation Method of improving the availability of a computer clustering system through the use of a network medium link state function
US6810396B1 (en) * 2000-03-09 2004-10-26 Emc Corporation Managed access of a backup storage system coupled to a network
US6845395B1 (en) * 1999-06-30 2005-01-18 Emc Corporation Method and apparatus for identifying network devices on a storage network
US20050055444A1 (en) * 2001-07-06 2005-03-10 Krishnan Venkatasubramanian Systems and methods of information backup
US6871296B2 (en) * 2000-12-29 2005-03-22 International Business Machines Corporation Highly available TCP systems with fail over connections

Patent Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6356977B2 (en) * 1995-09-01 2002-03-12 Emc Corporation System and method for on-line, real time, data migration
US6101497A (en) * 1996-05-31 2000-08-08 Emc Corporation Method and apparatus for independent and simultaneous access to a common data set
US20030126200A1 (en) * 1996-08-02 2003-07-03 Wolff James J. Dynamic load balancing of a network of client and server computer
US5966730A (en) * 1996-10-30 1999-10-12 Dantz Development Corporation Backup system for computer network incorporating opportunistic backup by prioritizing least recently backed up computer or computer storage medium
US6108300A (en) * 1997-05-02 2000-08-22 Cisco Technology, Inc Method and apparatus for transparently providing a failover network device
JPH1124846A (ja) 1997-07-03 1999-01-29 Hitachi Ltd ネットワークを利用したバックアップシステム
US20010020254A1 (en) * 1998-06-30 2001-09-06 Blumenau Steven M. Method and apparatus for managing access to storage devices in a storage system with access control
US6845395B1 (en) * 1999-06-30 2005-01-18 Emc Corporation Method and apparatus for identifying network devices on a storage network
US6810396B1 (en) * 2000-03-09 2004-10-26 Emc Corporation Managed access of a backup storage system coupled to a network
US20010056438A1 (en) * 2000-06-27 2001-12-27 Atsuki Ito Database system with backup and recovery mechanisms
US6785678B2 (en) * 2000-12-21 2004-08-31 Emc Corporation Method of improving the availability of a computer clustering system through the use of a network medium link state function
US6871296B2 (en) * 2000-12-29 2005-03-22 International Business Machines Corporation Highly available TCP systems with fail over connections
US20020176430A1 (en) * 2001-01-25 2002-11-28 Sangha Onkar S. Buffer management for communication systems
US20020161845A1 (en) * 2001-04-30 2002-10-31 Odenwald Louis H. Selectable logical identifier mapping
US20050055444A1 (en) * 2001-07-06 2005-03-10 Krishnan Venkatasubramanian Systems and methods of information backup
US20050172093A1 (en) * 2001-07-06 2005-08-04 Computer Associates Think, Inc. Systems and methods of information backup
US20030084076A1 (en) * 2001-10-31 2003-05-01 Shihoko Sekiguchi Method for storage management of storage resource on a storage network
US20030120723A1 (en) * 2001-12-20 2003-06-26 Bright Jonathan D. System and method for distributed network data storage
US20030126282A1 (en) * 2001-12-29 2003-07-03 International Business Machines Corporation System and method for improving backup performance of media and dynamic ready to transfer control mechanism

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Tierney et al., A nework-Aware distributed storage cache for data intensive environments, High performance distributed computing, 1999, proceedings, The eighth international symposium on Aug. 3-6, 1999, pp. 185-193. *

Cited By (44)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080205441A1 (en) * 2003-05-08 2008-08-28 Scott Furey Data frame processing
US8170035B2 (en) 2003-05-08 2012-05-01 Qualcomm Incorporated Data frame processing
US20090077232A1 (en) * 2003-10-14 2009-03-19 International Business Machines Corporation Remote activity monitoring
US7725579B2 (en) * 2003-10-14 2010-05-25 International Business Machines Corporation Computer readable medium and system for remote activity monitoring
US8949614B1 (en) * 2008-04-18 2015-02-03 Netapp, Inc. Highly efficient guarantee of data consistency
US8769186B2 (en) 2008-08-08 2014-07-01 Amazon Technologies, Inc. Providing executing programs with reliable access to non-local block data storage
US20100036850A1 (en) * 2008-08-08 2010-02-11 Garman Matthew S Providing executing programs with reliable access to non-local block data storage
US9262273B2 (en) 2008-08-08 2016-02-16 Amazon Technologies, Inc. Providing executing programs with reliable access to non-local block data storage
US8015343B2 (en) * 2008-08-08 2011-09-06 Amazon Technologies, Inc. Providing executing programs with reliable access to non-local block data storage
US9727473B2 (en) * 2008-09-30 2017-08-08 Intel Corporation Methods to communicate a timestamp to a storage system
US20100082995A1 (en) * 2008-09-30 2010-04-01 Brian Dees Methods to communicate a timestamp to a storage system
US10261701B2 (en) 2008-09-30 2019-04-16 Intel Corporation Methods to communicate a timestamp to a storage system
US20100199000A1 (en) * 2009-02-05 2010-08-05 Htc Corporation Data storage device and method for operating the same
US11449394B2 (en) 2010-06-04 2022-09-20 Commvault Systems, Inc. Failover systems and methods for performing backup operations, including heterogeneous indexing and load balancing of backup and indexing resources
US10990484B2 (en) 2010-06-04 2021-04-27 Commvault Systems, Inc. Performing backup operations and indexing backup data
US12001295B2 (en) 2010-06-04 2024-06-04 Commvault Systems, Inc. Heterogeneous indexing and load balancing of backup and indexing resources
US10534673B2 (en) 2010-06-04 2020-01-14 Commvault Systems, Inc. Failover systems and methods for performing backup operations
US11099943B2 (en) 2010-06-04 2021-08-24 Commvault Systems, Inc. Indexing backup data generated in backup operations
US20110320509A1 (en) * 2010-06-29 2011-12-29 France Telecom Managing the site where data is stored in a distributed storage system
US8738583B2 (en) * 2011-02-09 2014-05-27 Cisco Technology, Inc. Efficiently delivering event messages using compiled indexing and paginated reporting
US20120203794A1 (en) * 2011-02-09 2012-08-09 Roulei Zhang Efficiently delivering event messages using compiled indexing and paginated reporting
US9483363B2 (en) 2013-05-08 2016-11-01 Commvault Systems, Inc. Use of temporary secondary copies in failover operations
US9483362B2 (en) 2013-05-08 2016-11-01 Commvault Systems, Inc. Use of auxiliary data protection software in failover operations
US9483364B2 (en) 2013-05-08 2016-11-01 Commvault Systems, Inc. Synchronization of local secondary copies with a remote storage management component
US9483361B2 (en) 2013-05-08 2016-11-01 Commvault Systems, Inc. Information management cell with failover management capability
US10001935B2 (en) 2013-05-08 2018-06-19 Commvault Systems, Inc. Use of auxiliary data protection software in failover operations
US10365839B2 (en) 2013-05-08 2019-07-30 Commvault Systems, Inc. Use of auxiliary data protection software in failover operations
US10884635B2 (en) 2013-05-08 2021-01-05 Commvault Systems, Inc. Use of auxiliary data protection software in failover operations
US9811427B2 (en) 2014-04-02 2017-11-07 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US9563518B2 (en) * 2014-04-02 2017-02-07 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US10534672B2 (en) 2014-04-02 2020-01-14 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US10013314B2 (en) * 2014-04-02 2018-07-03 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US20170091049A1 (en) * 2014-04-02 2017-03-30 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US20150286537A1 (en) * 2014-04-02 2015-10-08 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US11321189B2 (en) 2014-04-02 2022-05-03 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US10838824B2 (en) * 2014-04-02 2020-11-17 Commvault Systems, Inc. Information management by a media agent in the absence of communications with a storage manager
US11429499B2 (en) 2016-09-30 2022-08-30 Commvault Systems, Inc. Heartbeat monitoring of virtual machines for initiating failover operations in a data storage management system, including operations by a master monitor node
US11550680B2 (en) 2018-12-06 2023-01-10 Commvault Systems, Inc. Assigning backup resources in a data storage management system based on failover of partnered data storage resources
US11200124B2 (en) 2018-12-06 2021-12-14 Commvault Systems, Inc. Assigning backup resources based on failover of partnered data storage servers in a data storage management system
US11663099B2 (en) 2020-03-26 2023-05-30 Commvault Systems, Inc. Snapshot-based disaster recovery orchestration of virtual machine failover and failback operations
US12235744B2 (en) 2020-03-26 2025-02-25 Commvault Systems, Inc. Snapshot-based disaster recovery orchestration of virtual machine failover and failback operations
US11645175B2 (en) 2021-02-12 2023-05-09 Commvault Systems, Inc. Automatic failover of a storage manager
US12056026B2 (en) 2021-02-12 2024-08-06 Commvault Systems, Inc. Automatic failover of a storage manager
US12360942B2 (en) 2023-01-19 2025-07-15 Commvault Systems, Inc. Selection of a simulated archiving plan for a desired dataset

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